On Tue, Feb 16, 2021 at 01:31:00AM +0100, Lino Sanfilippo wrote:
>
> +static int tpm_add_tpm2_char_device(struct tpm_chip *chip)
> +{
> + int rc;
> +
> + device_initialize(&chip->devs);
> + chip->devs.parent = chip->dev.parent;
> + chip->devs.class = tpmrm_class;
> +
> + rc = dev_set_name(&chip->devs, "tpmrm%d", chip->dev_num);
> + if (rc)
> + goto out_put_devs;
> + /*
> + * get extra reference on main device to hold on behalf of devs.
> + * This holds the chip structure while cdevs is in use. The
> + * corresponding put is in the tpm_devs_release.
> + */
> + get_device(&chip->dev);
> + chip->devs.release = tpm_devs_release;
> + chip->devs.devt =
> + MKDEV(MAJOR(tpm_devt), chip->dev_num + TPM_NUM_DEVICES);
> + cdev_init(&chip->cdevs, &tpmrm_fops);
> + chip->cdevs.owner = THIS_MODULE;
> +
> + rc = cdev_device_add(&chip->cdevs, &chip->devs);
> + if (rc) {
> + dev_err(&chip->devs,
> + "unable to cdev_device_add() %s, major %d, minor %d,
> err=%d\n",
> + dev_name(&chip->devs), MAJOR(chip->devs.devt),
> + MINOR(chip->devs.devt), rc);
> + goto out_put_devs;
> + }
> +
> + return 0;
> +
> +out_put_devs:
> + put_device(&chip->devs);
I'd rather you organize this so chip->devs.release and the get_device
is always sent instead of having the possiblity for a put_device that
doesn't call release
Jason
